Burner apparatus for liquid fuel



March 30, 1965 G. E. POWELL BURNER APPARATUS FOR LQUID FUEL Filed Nov. 21, 19Go lNvEN-rok GERALD a. POWELL BY M2M, M, am@ L uw ATTORNEYS United States Patent O 3,175,600 BURNER APPARATUS FOR LIQUID FUEL Gerald Everett Powell, Shoreham-by-Sea, England,

assignor to Ricardo & Co., Engineers (1927) Limited., London., England, a company of Great Britain Filed Nov. 21, 1960, Ser. No. 70,850 Claims priority, application Great Britain, Nov. 23, 1959, 39,707 59 8 Claims. (Cl. 158-4) This invention relates to combustion apparatus for liquid fuel and is particularly applicable to combustion chambers of the kind having an air inlet at one end and an outlet for the products of combustion at the other, and including primary and secondary zones which cornmunicate with one another at their adjacent ends, fuel being injected into the primary zone and the flow through the two zones being such that a proportion of the products of combustion and unburnt air ow continuously from the outlet end of Ithe secondary zone through the primary zone to the inlet end of the secondary zone, where fresh air also enters the secondary zone, whereby the fuel is injected into a mixture of air and combustion products in the primary zone so as to tend to be vaporized before entering the secondary zone. Such a combustion chamber is shown in the present applicants U.S. Patent Serial No. 2,882,843.

According to the present invention combustion apparatus for liquid fuel comprises a tubular combustion chamber of the kind set forth, including rotary impeller means arranged between the primary and secondary zones which controls the gas flow through the primary zone and into the secondary zone, and a centrifugal rotary fuel distributing device arranged to distribute fuel into the primary zone and which is rotated with the impeller means.

The two zones are preferably separated by a wall concentric with a rotary distributing part of the centrifugal rotary fuel distributing device and the rotary impeller means comprises a rotor having impeller blades which are arranged to rotate with said rotary distributing part and which lies adjacent to the outlet of the primary zone defined by the end of the wall which separates the two zones through which gas flows into the inlet end of the secondary zone from the adjacent end of the primary zone.

Control apparatus may be included for varying the rate of flow of fuel delivered by the centrifugal rotary fuel distribution device and the volumetric rate of flow of gas from the primary to the secondary zones in synchronism for a given speed of rotation, and in a preferred arrangement the apparatus for varying the volumetric rate of ow to the secondary zone from the primary zone acts to move the impeller rotor axially in relation to the outlet from the primary zone defined by the end of the wall separating the two zones.

In a convenient arrangement the centrifugal rotary fuel distributing device includes liquid metering apparatus of the kind wherein the liquid rises up the sides of a rotatable vertical tube.

If such apparatus is used then the impeller rotor may be connected to the rotatable vertical -tube of the liquid metering apparatus, and the rotary distributing part of the rotary fuel distributing device may be in the form of a plate or disc of perforated metal secured in axial alignment to the u pper end ofthe rotatable vertical tube. The arrangement is conveniently such that axial movement of the impeller rotor moves the blades relative to the outlet from the primary zone so that they cause more or less gas to be'recirculated, that is to say drawn through the outlet from the primary zone and discharged to the secondary zone.

3,175,600 Patented Mar. 30, 1965 lCC Preferably the control apparatus acts to move the rotatable tube axially relative to the outlet of the primary zone and also acts to cause axial movement of the inner control spill pipe of the liquid metering apparatus to vary the rate of fuel delivery in a predetermined manner.

Second impeller means coaxial with the impeller means referred to above may also be included which act to control the ow of fresh combustion air from the atmosphere into the inlet end of the secondary zone.

This second impellermay in this case comprise a rotor having impeller blades situated below and connected to the first impeller rotor.

The invention may be performed in various ways but one embodiment including a centrifugal rotary fuel distributing device including liquid metering apparatus will now be described by way of example. The accompanying drawing shows in detail a cross-section of the liquid fuel burner apparatus.

The combustion apparatus to be described is for use with a small waterboiler of a domestic hot water or central heating system. The combustion chamber is of annular form and comprises an outer cup like shell indicated generally at 1 the upper end of which is open and the lower end of which is formed with a large diameter intake bore 2 through which combustion air to be burnt in the combustion chamber can be drawn in the direction of the gas ow being indicated by arrows A. The shell 1 comprises a cylindrical outer part 3 to which is rigidly attached a dished inner part 4 which forms the lower part of .the shell, the cylindrical outer part 3 having a downward extension or skirt 5 which serves to support the cup like shell 1 from a horizontal bed plate 6 to which it is secured. Arranged concentrically within and secured to the outer part 3 is a frusto-conical battle 7 the wider upper end of which is connected to the upper periphery of the part 3 while its lower end is connected to an annular baille ring 8 spaced from the part 4 by supports (not shown) to provide a tapering air passage 10 between ythe frusto-conical baille 7 and the part 4, into which passage 10 a proportion of the incoming combustion air can be diverted, the remainder passing into the combustion space 11 through the ring 8. The frusto-conical baille 7 is provided with a series of holes 12 through which air passing through .the passage 10 between the balile and the outer shell can also enter the combustion space 11. The annular baffle ring 8 is displaced upwardly somewhat from the lower end of the part 4 and an annular cup shaped deector 13 of smaller diameter is positioned slightly lower than the baille ring 8 and overlaps this baffle ring 8 to ensure that combustion air entering through the large diameter intake port 2 passes upwards through the space between the annular deflector 13 and the part 4 and is divided by the annular baflie ring 8 into two streams one of which enters the tapering air passage 10 while the other enters the combustion space 11 directly through the annular space between the annular dellector 13 andthe annular baffle ring 8 as set forth above. An annular wall 14 is provided within the combustion space 11 which is maintained coaxially by tangential supports 15 extending between it and the annular bafe 13. The lower end of the Wall 14 is formed with an inwardly extending flange 16, and the outer diameter of the wall is somewhat greater than the diameter of the air intake bore 2. The bore defined by the internal flange 16 provides an outlet passage 17 from the space 18 defined within the wall.

A centrifugal rotary fuel distributing device 20 is arranged to rotate within the space defined by the annular wall 14 and includes liquid fuel metering apparatus comprising a liquid reservoir 21 which is secured beneath the bed plate 6 and which incorporates a fuel` level control device 22 of the type used in a conventional carburetor,

chamber @through which fuelpcan be I .1p to-'control a fuelrinlet port A ilow metering device in the form of atubular assem- 23 in the bed plate v6 1Vand comprises a rotatab-levertical tube referred to herein as YVthe outer pipe 24 which is of Y circular cross-section and the'lower part Vof which, referred' to hereinas thefuel pipeV 25," is of constant diameter and vertically 'supported to rotate Vas, hereinafter described,

flared, to constitute at*l its termination a lhorizontal lip Si.

' The outer pipe 24, 25 is surrounded by and'rigid with a co-axial tubular 'casing 32 which also extends into the reservoir 21 ythroughfthe bore 23 in the bed plate 6 and which is connected to Vthe outer pipe 24, 25 by a flange 55 at an intermediate point andv at its upper end. A sealing gland 33 surroundsthe vcasing 32 where it passes through the bed plate 6 torprevent the escape Vof fuel Vfrom the. reservoirfZl'. The assembly comprising' the outer pipe n 24, "25 and thetubular casing-32 is rotatably supported on upper andlower spaced bearings 26, Z71carried at the upper and lower ends of a vertical hollow stanchion 34 "armeno Y 23, `so that fuel is'maintained Y I at an approximately constant level in the reservoir 2l.

bly extends vertically from this chamber through a bore f is secured vto the outer surface Yof'kthespill pipe 4th a small working clearancev being provided between the helical member 555i and the innerV surface of thekfuel pipe 2s. The helical member Sti thus provides, between the lower halves of the fuel pipe 25-and Vthe spill pipe 40 a helical` passage the outer surface of which isformed by the rotatablefuel pipe 25 so that fuel isrdrawn upwards by frictional dragfrom the reservoir 21 towards 'and` into the outlet tube 28, A pair oftran-sversebores-Sl are also l provided Vinthe `wall ofthe fuelpipe Y25 Ywhere it merges into the frusto-conicalvoutlet`tube-23 through which there is a constant fuel bleed into a chamber 39a and thence to the Vannular pulleycooling chamber 39 fhroughV apertures 52 andout vof this chamberthrough openings 53and hence baclr tothe reservoir 21f by Way of an annular cooling passage 54 defined bythe space between the lower part of the outer casing` 32j and the stanchion 34. Fuel from thel chamber'39 also lubrcates f theV bearing 26 and then flows down a passage 54 to lubriwhich is supported by a spider in the form of a cylindrical member coaxial withthe stanchion and secured atV its upper end beneath the bed plate 6 while its lower end carries spacers v:isti which are connected to the lower end, l of the stanchion 34 so that it the bore 23 in the bed plate 6.

The stanchion 34 thus surroundsithe fuel'piper ,Z5-and' is surrounded by the lower end of the casing 32 the bearing 26 atY the upper end of the stanchion- 34 having an outer bearing surface so that it bears against the inner surface of the casing 32'and the lower bearing v-27 ,having an *innerV bearing surface engaging the outer lower end ofthe fuelpipe 25. The outer pipe 24 togetherV with its outercasing 32 can be rotated at a-constant speed about its axis byV an -electricmotor (not shown) mounted adjacent to the reservoirfZl and driving the casing 32 andV pipe 2li-through yayflat bolt` 37 acting on al pulley 33" formed onthel outside of the casing 32 where it surrounds the upper bearing 26.V space is left between the pulley 33 and the casing 32 to form an annular pulley cooling passed to cool the pulley as 'hereinafter described.

Mounted concentrically within'the fuelpipe 25 is a non-rotating vertically extending `andrvertically movable Vspill or overflow pipe 4i? the upper end 4l of which V'expasses coaxially through cate a thrust race 56 hereinafter again referred to in addition to flowing down a passagel betweenthe'stanchion 34 andthe fuel pipe 25 to lubricate the bearing 27.

The lower end of the casing 32 is provided with holes by which the fuel can escape from its lower end via the thrust race 56 into thenreservoir,V this thrust race being Y supported by aY flanged horizontal plate 57. The plate 57 Y is connected Yby a member 53 to a vertically extending rod 60 which passes through the base plate'6, y,sealing means el being provided to prevent the escape of fuel from Vthe f main Vfuel chamber 21. vr.The rod 6i) isfin'` line with theV rod 43 in the drawing,rand the `upper part of the rod 43 has therefore been omittedfin order that the rod 60 can be more clearly shown. The upper endV of the rod 6@ is pvotally connected to a leverf62 whichris'pivoted at an intermediate point 6,3! to'a support 64 connected to the y base plate 6, so that'the movement of the lever 62 about its intermediate vpivot point 673 'causesthe outer casing 32v Y togetherwith its associated outer pipe 24 tornoveverticallygi The; other'end of this lever 62Y`is connected 'tothe' 'operating rod 47 of .the control apparatus at thesarne jpoint as the lever 44 for 'movingthe overflow pipe 40,

but the distance from the intermediate pivot-63 is greater than that'from the pivot point 45 of the other lever 44 so that as thev outer casing 32 is moved Vverticallydownward the overflow pipe also movesY downward but to a fur- I ther extent so that the flow of fuel is reduced, the apparatends into the frusto-conical outlet tube 28, and the lowerV end of which protrudes beyond the Vlower end ofthe fuelV pipev 25 where it is secured to one end of a horizontally extending rigid`linkf42 the other end of which is adjustably connected to a vertically extending movable control rod 43 which Vcan be moved to adjustthe height of the yupper The upperend of this control rod 43 is pivoted tofone end of'a lever 44 which is itself pivotedat an intermediate tus working in a similar but opposite manner when the movement is reversed. Y Y Y The length of the pulley 33 is such that itallows the fiat driving belt 37 to move up andV down to allow for the different vertical positionsV ofV the pulley 33 when the casing 32 is moved and to allow thebelt' to remain end 41 of the spill pipe 40 withinA the outlettube 2S. Y

causes the spill pipe 4t) to be raised or lowered. Where the control rod 43 passes" through thebase. plate a sealing gland is provided toprevent the escape of fuel from the fuel chamber 2li.` VThe upper part ofthe rod 43 has been omitted Vfrom the drawing'in order that further apparatus which is in line withk can be seen'. Y f Y .I Y

The spill pipe 40 is located coaxially within the fuel pipe 24 by a helical memberf5ti which extends along and `it, and which is to be described, Y

radially in line with` the upper bearing 2,6.l t

y An impeller devicegis connected` to the outer Vcasing 32-the rotor of which 'impeller comprises a pair of annular discs 65, 66 vertically spaced from'one another along the length of the casing the lowerdisc 66 having an upwardly g extending flange 67 'ther rim of which `is connected to the upper Vdisc 65 at its outerperiphe'ryysothat the discs define an annular rotor cooling chamber 68 between them. AV ring of impeller blades 70 is secured `to the upper surface of the upper disc 65 and a similarring'of impeller blades 71 are secured tothe lower surface of the lower disct66, an annular baffle ,plateV 72 being connected to the lower edges of the lower ring of blades Y'71 so that an annular space, referred to herein as the intake orifice 73, is left between the outer casing SZQand the vinneredge of the annulardisc 72 which isturned downwards to form a flange ,which-defines the intakeport'Z. The rotor and its associated Virnpeller blades '70,` 71T are so vertically disposed and dimensioned that when the' outer casing 32 is in its highest vertical position theannular baiile plate 72 connectedrto'the lower ring `of yimpeller blades` 71 is substantially in line with the intalreiportZ.YV Y Similarly the peller blades 71 is connected is substantially in line with the lower end of the annular deilector 13 and the upper ring of impeller blades 70 is immediately beneath the inturned flange 16 of the annular wall 14, so that when the impeller is rotated air will be drawn by the blades 71 through the annular intake orifice 73 opening from the intake port 2 and delivered into the space between the annular dellector 13 and the shell 1 and hence into the space 11 both directly through the passage between the parts 8 and 13 and through the space 10, as indicated by the arrows A. At the same time there will be a gas flow, induced by the blades 70, from the space 11 into the upper end of the space 18 out of the lower end of this space and into the space 11 between the parts 16 and 13, as indicated by the arrows B. Holes 74 and 76 are provided in the casing 32 and holes 77 in theplate 66 so that air will be circulated through a cooling space 75 between the casing 32 and the part 28 above the pulley 38 and through the annular rotor cooling space 68 defined within the rotor, by reason of centrifugal force exerted on the air during rotation in the annular space 68.

The upper end of the outlet tube 28 is arranged to lie at an appropriate point within the inner wall 14 and the rotary distributing part of the centrifugal rotary fuel distributing device is in the form of a plate or disc 78 of perforated metal, for example expanded metal, secured in axial alignment with the upper end of the Outer tube 28 so that the liquid fuel will pass through the perforations and will be flung outwardly from the plate or disc 78 when the casing and outer tube are rotated. A small dome-shaped disc 80 is connected to the plate or disc 78 so that fuel only passes through the perforations in an annular space 81 between the upper end of the outer tube 28 and the dome-shaped disc 80.

The combustion chamber is of the type having primary and secondary zones. The primary zone is the space 18 within the annular wall 14 and the secondary zone is the space 11 between the annular wall 14 and the frustoconical baille 7. In operation fuel is delivered by the disc 78 into the primary zone 18 in which, as explained above, the flow is downwardly, and the lluid consists of a mixture of air, burning products of combustion and unburnt fuel. This mixture then llows through the passage 17 between the inturned flange 16 and the casing 32, radially outwards between the upper impeller blades 70 and into the secondary zone 11 where the mixture of fuel and gases mingle with additional combustion air drawn in through the intake orifice 2 by the lower blades 71 of the rotor. A further part of the total combustion air is delivered into the secondary zone 11 after passing through the tapered passage 1u and the holes 12 in the frusto-conical baflle 7 while the combustion products are finally exhausted through the open upper end of the combustion space 11. There is thus a constant recirculation of part of the burning products down through the part 11 and it is into these burning products that the fuel is delivered, thus tending to vaporize the fuel before it reaches the zone 11.

When the electric motor is started it rotates the casing 32 causing the impeller rotor to rotate and thus create the necessary llow of combustion air into the combustion chamber as a whole and the re-circulation flow within that chamber itself. It also causes fuel to be drawn up the helical passage deiined by the helical member 50 and delivered through the annular space between the upper ends of the fuel pipe 28 and the overflow pipe 40 to the interior of the outlet tube 28. The fuel within the outlet tube 28 tends to rise up the inner wall of the tube so that the surface of the fuel is in the general form of a concave meniscus, having its center at the upper end 41 of the spill pipe 40 so that the level of the meniscus is determined by the level of the upper end 41 of the overllow pipe 40. The outermost and highest part of the meniscus extends to the upper end of the outlet tube 28 where the fuel is tlung radially outwards across the perforated plate or disc- 6 78 and into the primary zone of the combustion chamber by centrifugal force where it is initially ignited by suitable means (not shown).

The rate at which the fuel is delivered by centrifugal force from the upper end of the fuel pipe 28 thus depends upon the speed of rotation and upon the vertical position of the upper end 41 of the overflow tube 40 which controls the level of the fuel in the outlet tube 28.

The spiral member 50 is thus so designed that its pumping action is sullicient to supply fuel continuously to the outlet tube 28 at least equal to and preferably greater than the maximum rate that fuel is required to llow out of the outlet tube 28 in addition to providing a suilicient ilow of fuel through the transverse bores 51 in the fuel pipe 28 to provide the necessary cooling llow behind the pulley 38 and the outer casing and to lubricate the bearings 26, 27 excess fuel flowing down the overflow tube 40.

It will be appreciated that if the overflow tube 40 is raised, the vertical position of the central, lowest part of the fuel meniscus in the outlet tube 28 rises correspondingly, and the rate at which fuel is flung out of the outlet tube 28 increases while the llow of excess fuel into the overflow pipe 40 decreases. If the overllow pipe 40 is lowered, the vertical position of the central, lowest part of the fuel meniscus drops correspondingly, the rate at which fuel is flung out of the outlet tube 28 decreases, and the ilow of excess fuel into the overow pipe 40 increases. Thus the rate of delivery of fuel into the combustion chamber is independent of the precise rate of delivery of fuel by the spiral member 50.

When maximum heat is required from the combustion chamber the overflow tube 40 will be in its uppermost position as will the outer casing 32 to which the impeller rotor is connected so that there is a maximum llow -of combustion air into and within the combustion chamber to supply the necessary ilow required for the maximum fuel distribution conditions.

If the heating requirement is reduced the outer casing 32 including the impeller rotor 15 moved downwardly away from the combustion chamber so that the upper impeller blades move away from the inturned ilange 16 of the inner wall 14 rendering them less effective and producing a reduced reversed gas llow through the primary zone inside the inner wall 14. At the same time the lower impeller blades 71 similarly move out of alignment with the annular space between the annular deflector 13 and the outer shell 1 so that they draw less combustion air into the combustion chamber. The overilow pipe 40 is simultaneously lowered to an even greater extent than the outer pipe 28 so that the fuel ilow is also reduced. The arrangement is such that when the outer casing 32 and its associated rotor are in their lowermost positions the lower impeller blades 71 are clear of the outer shell 1 so that there is no induced flow into the combustion chamber of combustion air, and the upper impeller blades are sulliciently far away from the lower flange 16 of the inner Wall 14 for their effect to be so considerably reduced as to be almost negligible. In these conditions the llame in the combustion chamber is reduced to a small annular ring on the perforated disc 78 close to the upper end of the fuel pipe 28 where the fuel continues to burn whilst creating very little heat in the combustion chamber.

It will be appreciated that a small llame of the type described above may be allowed to burn for a very great length of time with only a small consumption of fuel and that if heat is required from the combustion chamber it is immediately available merely by operating the member 47 to move the outer casing 32 together with its associated rotor and the spill pipe 40 upwardly to the appropriate position. When such a device is employed with a domestic boiler the member 47 can be connected to a thermostat so that the heat generated in the combustion chamber can be varied to keep the water in the boiler at a desired temperature.

i fWhat'I claim las my invention and desire to secure byV VLetters Patent is: A .a p

l. Combustion apparatus vcomprising a combustionV chamber of open-ended tubular'form having an air inlet at one end and an outlet for theproducts of` combustion almeno maryzone which communicate with one another at their adjacent fends, a rotary fuel distributing.devicearranged toV distribute fuel into said primary Zone, control means operativeV to vary the rate of flowv of fuel delivered by said rotary fuel .distributing device and theV volumetric rate of Afluid flow from said primary zone to said secondary Zone, effected in they same sense and in synchronism, and

' rotary combustion-product impeller means arranged'between said primary and secondary zones and comprising impeller blades which are operatively arranged to rotate Withrsaid'rotaryV fuel distributing device and which lie adjacent to theend of said annular wall adjacent to said air inletto causera proportion of the products of combustion and unburntairto flow continuously from the end of the secondary zone which lies adjacent to the said outlet for the products Vof `combustion through thepri-Y `i mary vzoneto the end of said secondary zone .which liesV adjacent to the said air inlet and Where, thereforeyfresh air from the'air inlet also enters said secondary zone.

2.v Combustion apparatus as claimed in claim 1Y in Y whiclrsaid control means'moves said rotary combustionproduct impeller means axially in relation to the adjacent end of said annular Wall.VV

3. Combustion apparatus as claimed, in claim 2 including air impeller means coaxial Withsaid combustion-product impeller means and operatively Controlling the,` flow of combustion air from the atmosphere into the end of said secondary Zone adjacent to said air inlet in accordance with speed of rotation. 1

f 4. Combustion apparatus as claimed in elaim` 3 in which said air impeller means comprises impeller blades situated belowvand attached to the said combustion-product'impeller means. V 5a. Combustion apparatus comprising a combustion chamber of open-ended tubular form having an airinlet at one end and an outlet for the products of combustion at its other end, `an Vannular dividing wall arranged coaxially Within the combustion chamber and dividing it into an outer annular secondary zone and an inner primary zone and where, therefore, Ifresh air 'l enterssaid secondary zone.

which lies adjacent to Vthe said outlet for the products of combustion through thev primary zone tothe'end of Vsaid -secondary'zone which lies adjacent to the said vair inlet .from the air inlet also 6. Combustion apparatus as claimed in' claim 5 in which said combustion-product impeller means Vis attached t0 .said rotatable'` tube .of said metering meansY and rotates therewith.

7. Combustion 'apparatus -as clainie'din claim 6 wherein, in said spill device said' spill pipe is mounted for vertical adjustment within said rotatable tube to'vary the fuel level maintained in saidl rotatable Atube and including control means operatively connected to said spillpipe and to'said combustion-product impeller Vmeans to vary simultaneously the vertical position to said spill pipe randY the vertical position of said combustion-product impeller means relatively to the adjacent end of said annularwallto vary the flow yof combustion products throughsaid combustionproduct impeller means. L

8. Combustion apparatus comprising a tubular combustion chamberhaving an: airiinle't at one end and an outlet for the products of combustion at its other end, an annular dividing Wall arranged Within andcoaxiallywith the combustion chamber to divide it into an outer annular sec- Vdisposed Within said deviceV and mounted forV vertical adjustment therein to. vary the level of fuel maintained in which communicate with one another at their adjacent ends, a'rotaryjfuel'distributing Vdevice comprising fuel metering means comprising a tube, means verticallysupporting said tube for rotation about its longitudinal axis,

fuel delivery means supplying fuelto the'interio'r of said f tube, driving means for rotating said tube, and a control V device controlling the rate 4of fuel ejection from the upper end of said tube when said tube is rotated, said control device( comprising a spill vdevice having. a spill pipe arranged with its inlet 'adjacent to the axis .of rotation of said ,tube and thusl determining thev level of fuel within said Y Atube at the axis of 'said tube, said device arranged todistribute fuel into said primary zone and rotary combustionproduct impellervrneans arranged between said primary and secondary zones and comprisingimpeller blades which are operatively arranged to rotate With said rotary fuel distributing device and'which lieadjacent to the end of said annular Wall adjacent to saidair inletk to cause a proportion of the products of combustion and vunburnt air to flow continuously from the end of theV secondary `zone said tube, a'perforatedV rotary distributing plate secured to the upper end .of said rotatable tube, combustion-product impeller means rotatable vvvith said rotatable tube and causing a proportion ofthe products -of combustionand Vunburnt aiuto flow'continuously lfrom the said lprimary zone` into the end of saidsec'ondary Zone adjacent to said air inlet andrair impeller means rotatable with said rotatable tube delivering freshairrfrom the'said air inlet into the adjacent end of said secondary zone.

v YReferences Citedthe Examiner Y .UNITED STATES PATENTS 1,584,045 I 5/26 Smith 158--77 1,762,242 6/30 Rodier 158-77 1,769,008 7/30 Vi/inklelA 158-77 Y .1,861,953 6/32 Chadwick et al.A 158-77 1,879,011 9/32 Appel ;;15s4 1,996,336 4/35 Junkers 158-4 2,072,587 3/37 Greenawalt 158-77 2,200,278 5/40l Johnston; Y

2,893,480 -7/59 McGillis etf al. Y 3,021,892 2/62` Brola 158-77 3,039,700 6/62V Powell 103-99 X FOREIGN PATENTS 452,795 11/48 ACanada.` l

`823,755 Y10/57 France..Y

n IAMESKW. WESTHAVER, Primary Examiner.

PERCVY L. PATRICK, ALDEN D. STEWART,

j 'Y Examiners, 

1. COMBUSTION APPARATUS COMPRISING A COMBUSTION CHAMBER OF OPEN-ENDED TUBULAR FORM HAVING AN AIR INLET AT ONE END AND AN OUTLET FOR THE PRODUCTS OF COMBUSTION AT ITS OTHER END, AN ANNULAR DIVIDING WALL ARRANGED COAXIALLY WITHIN THE COMBUSTION CHAMBER AND DIVIDING IT INTO AN OUTER ANNULAR SECONDARY ZONE AND AN INNER PRIMARY ZONE WHICH COMMUNICATE WITH ONE ANOTHER AT THEIR ADJACENT ENDS, A ROTARY FUEL DISTRIBUTING DEVICE ARRANGED TO DISTRIBUTE FUEL INTO SAID PRIMARY ZONE, CONTROL MEANS OPERATIVE TO VARY THE RATE OF FLOW OF FUEL DELIVERED BY SAID ROTARY FUEL DISTRIBUTING DEVICE AND THE VOLUMETRIC RATE OF FLUID FLOW FROM SAID PRIMARY ZONE TO SAID SECONDARY ZONE, EFFECTED IN THE SAME SENSE AND IN SYNCHRONISM, AND ROTARY COMBUSTION-PRODUCT IMPELLER MEANS ARRANGED BETWEEN SAID PRIMARY AND SECONDARY ZONES AND COMPRISING IMPELLER BLADES WHICH ARE OPERATIVELY ARRANGED TO ROTATE WITH SAID ROTARY FUEL DISTRIBUTING DEVICE AND WHICH LIE ADJACENT TO THE END OF SAID ANNULAR WALL ADJACENT TO SAID AIR INLET TO CAUSE A PROPORTION OF THE PRODUCTS OF COMBUSTION AND UNBURNT AIR TO FLOW CONTINUOUSLY FROM THE END OF THE SECONDARY ZONE WHICH LIES ADJACENT TO THE SAID OUTLET FOR THE PRODUCTS OF COMBUSTION THROUGH THE PRIMARY ZONE TO THE END OF SAID SECONDARY ZONE WHICH LIES ADJACENT TO THE SAID AIR INLET AND WHERE, THEREFOR, FRESH AIR FROM THE AIR INLET ALSO ENTERS SAID SECONDARY ZONE. 